For coping with recent global warming, there have been needs smaller-sized and higher-output rotating electrical machines. As such rotating electrical machines, example, there have been known rotating electrical machines having a stator core including a plurality of slots opened in their inner periphery side, and a plurality of segment conductors with a substantially-U shape which are inserted in the respective slots, thereby increasing the space factor for increasing the cooling performance for realizing higher outputs.
Further, there have been stators vehicle AC electric generators which include a first coil end group having turn portions formed therein, and a second coil end group having a plurality of bonded portions placed therein, wherein these bonded portions are constituted by tip end portions bonded to each other, wherein a first resin material with a smaller thickness is adhered to the first coil end group and the second coil end group, and a second resin material with a larger thickness is adhered to only the vicinity of the bonded portions in the second coil end group, in order to improve the insulation performance (refer to PTL 1, for example).
Further, there have been electrical apparatuses in which the material of the second resin material used at the bonded portions is specified (refer to PTL 2, for example).